Dovetail fixtures of the type envisioned herein are described in U.S. Pat. Nos. 1,679,074, 2,764,191, 3,057,383, 3,109,466, 3,800,840, 3,834,435 and in other patents. Such fixtures include a horizontal table and a vertical apron equipped with independent clamps by which the two work pieces, such as a drawer, box or bookcase sides and the like, can be rigidly held at right angles. A slotted guide member in the form of a comb or template is held against one of the work pieces to guide a router or similar cutting tool as the bit thereof traces the dovetail pattern. It has become standardized practice to provide such fixtures wherein the slotted guide member in the form of a comb or template has two selectable pitches or spacings for the fingers and slots thereof, enabling the making of the mating tenons and mortises as either a half inch pitch joint or a quarter inch pitch joint. Although it has been previously suggested, in the aforesaid U.S. Pat. No. 3,800,840, for example, to provide the comb-like fingers or teeth on different edges of the same template member, in such previously known fixtures it has been necessary to completely remove various screws, or the like, and reinsert the same in changing tool guidance from one template edge to another. Such operation is burdensome to the operator and the small screws, or the like, that must be removed and replaced are susceptible to being easily lost.